KANBAN

Kanban is a method through which Just In Time is achieved.

Kanban (かんばん(看板)^?) (literally signboard or billboard in Japanese) is a scheduling system for lean and just-in-time (JIT) production. Kanban is a system to control the logistical chain from a production point of view, and is not an inventory control system. Kanban was developed by Taiichi Ohno, at Toyota, as a system to improve and maintain a high level of production.

In the Toyota Production System, a unique production control method called the “kanban system” plays an integral role. The kanban system has also been called the “Supermarket method” because the idea behind it was borrowed from supermarkets. Such mass merchandizing stores use product control cards upon which product-related information, such as a product’s name, code and storage location, are entered. Because Toyota employed kanban signs for use in their production processes, the method came to be called the “kanban system.” At Toyota, when a process refers to a preceding process to retrieve parts, it uses a kanban to communicate which parts have been used.

Why use a supermarket concept

A supermarket stocks the items needed by its customers when they are needed in the quantity needed, and has all of these items available for sale at any given time.
Taiichi Ohno (a former Toyota vice president), who promoted the idea of Just-in-Time, applied this concept, equating the supermarket and the customer with the preceding process and the next process, respectively. By having the next process (the customer) go to the preceding process (the supermarket) to retrieve the necessary parts when they are needed and in the amount needed, it was possible to improve upon the existing inefficient production system. No longer were the preceding processes making excess parts and delivering them to the next process.

The 6 steps to get started with Kanban

1. Map your value stream (your development process).
   Where do feature ideas come from? What are all the steps that the idea goes through until it’s sitting in the hands of the end-user?
2. Define the start and end points for the Kanban system.
   These should preferably be where you have political control. Don’t worry too much about starting with a narrow focus, as people outside the span will soon ask to join in.
3. Agree:
   • Initial Work In Progress limits and policies for changing or temporarily breaking them
   • Process for prioritising and selecting features
   • Policies for different classes of service (e.g. “standard”, “expedite”, “fixed delivery date”). Are estimates needed? When choosing work, which will be selected first?
   • Frequency of reviews
4. Draw up a Kanban board.
   All you need is a whiteboard and some Post-It notes. Don’t spend too much time making it look beautiful because it will almost certainly evolve.
5. Start using it.
6. Empirically adjust.